The present invention relates to a curable silicone composition, and in particular to a curable silicone composition useful in forming a coating film having a low surface energy. 2 Description of the Prior Art
In recent years, pressure sensitive adhesives containing a dimethylpolysiloxane as the main component are used for extensive purposes because of their heat resistance, cold resistance, chemical resistance and electrical insulation property. They are also used in the medical field because of the non-toxicity.
However, since the adhesives have extremely strong adhesion, conventional release agents comprising a curable silicone cannot offer sufficient release properties. Particularly, if tapes or labels having a pressure sensitive adhesive layer containing a dimethylpolysiloxane as a main component are stored for a long term, the release force needed to peel the tape or label from the back of the tape or a support will increase markedly. Consequently, when peeling takes place, the pressure sensitive adhesive layer or the release agent layer is broken, so that the pressure sensitive adhesive tape or the label becomes useless. As a curable silicone that can exhibits high release properties against such dimethylpolysiloxane-based pressure sensitive adhesives having a strong adhesion, there is known one comprised of an organopolysiloxane containing a fluorine-containing substituent having the formula: C.sub.n F.sub.2n+1 CH.sub.2 CH.sub.2--, where n is an integer of 1 or more (Japanese Pre-examination Patent Publication (KOKAI) Nos. 225581/1987 and 320/1988). This curable silicone, however, does not have sufficient release properties as a release agent for the above pressure sensitive adhesive, either.